Workpapers are the evidence trail behind professional work. In tax practice they include source documents, schedules, calculations, notes on judgments made, and the reviewer's comments. They allow a reviewer to check the work, help the firm answer questions later, and support the return if a taxing authority examines it.
The strongest workpapers link each figure to its source. When a reviewer can click from a number to the page of the document it came from, review is faster and more reliable. Firms should also follow a retention policy so workpapers are kept long enough to support the return and disposed of securely afterward.